You would probably know Sandra Boynton's work if you saw it. You might remember her (possibly) most famous design "Things are getting worse...Please send chocolate!" I believe her "Wee fish, ewe, a mare, egrets, moose..." card was released before 1982. I remember sending it out as my Christmas card before my father died in May of 1983. Sandra Boynton made her name as a greeting card artist who used cartoon animals for all of her work.

I just double-checked some history on Sandra Boynton's work, and her "Wee fish, ewe, a mare, egrets, moose..." coffee mug was released more than 27 years ago, and the wrapping paper was released roughly 30 years ago (1980), and both followed her wildly successful Christmas card in which the artwork first appeared, so I believe it was her copyrighted work before 1982. :-)